Explain the problem. The Public Service Commission no longer has the authority to accept as many of the consumer telecommunications complaints as we have in the past.To file a consumer complaint online, please click below, fill out the form and click "Send. 1. Contact the company's customer service or escalation department. 2. Use consumer protection websites or forums. 3. General Inquiries or Complaints. 3 samples of complaint letters you can use to draw inspiration from. Be clear and concise. Describe the item or service you bought and the problem. What is the email address for me to send a written complaint about customer service?